1. Field of the Invention
The present invention concerns data processing and medical technology and in particular concerns the setup of imaging apparatuses, for example magnetic resonance tomography systems.
2. Description of the Prior Art
Within the scope of an examination with imaging apparatuses in clinical practice—for example for magnetic resonance tomography (MRT), computed tomography (CT), positron emission tomography (PET) or other nuclear medicine apparatuses—the necessity arises to adapt the protocol parameters of a measurement protocol to patient-specific values and to other examination variables. For example, specific measurement protocol parameters must be adapted to the respective lung retention volume or to EKG values of the patient. These values vary from case to case and can often only be registered immediately before the respective examination or measurement (data acquisition).
In the interim, in clinical practice a number of predefined measurement protocols have emerged as helpful measurement protocols. However, when these predefined measurement protocols must be adapted to specific variables and values, in known methods it is often the case that only suboptimal protocol settings are found, which leads to a lower image quality and ultimately to a reduced diagnostic value.
Different protocol parameters of a measurement protocol are defined depending on the type of the examined organ and on additional clinical and/or medical variables. Examples of such protocol parameters are the following variables: TE=echo time, TR=repetition time, FOV=field of view, slice thickness etc.
In order to optimize the determination of the measurement protocol parameters, it is known in the prior art to provide methods to automate MR measurement sequences. For example, an automated creation of MR measurement sequences for the examination of knee joints is tested in one study (see F. E. Lecouvet et al., “Clinical Evaluation of Automated Scan Prescription of Knee MR Images” in: Journal of Magnetic Resonance Imaging 29:141-145 (2009)). Further clinical studies are likewise concerned with an automated generation of an MR measurement protocol: T. Benner et al., “Comparison of Manual and Automatic Section Positioning of Brain MR Images” in “Radiology”, Vol. 239: No. 1—April 2006 and K. L. Weiss et al., “Automated Spine Survey Iterative Scan Technique” in “Radiology”, Vol. 239: No, 1—April 2006.
A common goal of the methods mentioned in detail in the preceding and other methods from the prior art is to achieve a measurement protocol can be automated.
However, it has proven to be a significant disadvantage that these known methods provide no opportunity for configuration on the part of the user. Rather, the user is directed to the predetermined values. However, an adaptation of an existing protocol to current values is in many cases necessary for clinical and/or medical reasons.
In the known methods from the prior art this problem was solved by requiring the operator of the MR scanner to determine patient-specific data (for example the air retention volume, the size of the patient, his position on the table, his heart rate etc.). The operator thereupon selects such an MR protocol that he or she deems to be best suited from a set of MR protocols. In a subsequent step, the operator must manually adapt specific protocol parameters, for example an acquisition time, to patient-specific values (for example to the lung retention volume or to the field of view) according to the patient's size. This method has proven to be both very time-consuming and extremely error-prone since the danger of incorrect inputs increases due to the manual influence.
It should be taken into account that the determination of a suitable measurement protocol with the respective protocol parameters is frequently a multidimensional problem. This is based on the fact that the determination of the protocol parameters is at least partially dependent on the protocol parameters themselves. In other words, the selection of a first protocol parameter can affect the determination of an additional protocol parameter.